Various wastes are produced in nuclear power plants, part of which are radioactive. The wastes have not been classified by activity, however, all of the wastes are considered to be so called low activity wastes. The greater part of the wastes consists of paper or other organic material. Table 1 below sets forth the composition of low activity wastes of IVO (the power company Imatran Voima Osakeyhtio). Different principles have been applied in classifying the wastes of TVO (the power company Teollisuuden Voima Osakeyhtio), as can be seen in Table 2 below).
TABLE 1 ______________________________________ Composition of the low activity waste accruing in the nuclear power plant of IVO. Type of Waste Quantity (kg per annum) ______________________________________ Paper 7500 Miscellaneous rag goods 1500 Plastics and rubber 700 Timber and wood 300 Total 1000 ______________________________________
TABLE 2 ______________________________________ Composition of the low activity waste accruing in the nuclear power plant of TVO. Type of Waste Quantity (kg per annum) ______________________________________ Paper/cardboard/wood 4000 Machine towels/cotton gloves/ overalls 4000 Fireproofed fabric 2000 Plastics and rubber 10000 Total 20000 ______________________________________
At the present time, wastes have been placed in barrels having a cpacity of about 200 liters. Assuming one barrel to hold 50 kg, the annual waste quantity, expressed in barrels, will be about 200 barrels at IVO and 400 at TVO. Thus, at the present, these two nuclear power plants alone, aggregate about 6000 barrels of low activity wastes for storage.
The original plans envisioned ultimate disposition of these wastes in spaces blasted out from bedrock. However, this is an expensive solution, and can give rise to various detrimental factors in the future. Thus, the organic material begins to decompose through the decades, producing various gaseous substances. The report "The Gas Production Due to Microbiological Activity in the VLJ Ultimate Disposal Facilities, Report UJT-84-16" estimates the quantity of gas formed to be several tens of cubic meters per annum during about 100 years.